In recent years, as an environmentally-friendly vehicle, an electric powered vehicle, such as an electric vehicle, a hybrid vehicle, a fuel-cell vehicle, and the like mounted with an electric storage device and a motor as a drive device are receiving attentions. In particular, in an electric powered vehicle, charging the electric storage device with a power source outside the vehicle (hereinafter, referred to as external power source) is proposed. Notably contribution of charging an electric storage device of an electric powered vehicle with midnight power on suppression of the total running cost and reduction in CO2 emission is expected.
There is a charger, as disclosed in Japanese Patent Laying-Open No. 10-262303 (Patent document 1), wherein a vehicle key of an electric car is in a form of an IC card and the IC card is inserted into the charger to thereby enable battery charging in a vehicle sharing system. In such a case, identification of a user of the charger is enabled, and use by third persons can be prevented.
Japanese Patent Laying-Open No. 2006-262570 (Patent document 2) proposes an electric power supply system that executes authentication and billing processes by transmission and reception of information using power line carrier communication in charging a battery of an electric vehicle. Concretely, by using a PLC (Power Line Communications) modem for inputting and outputting a power line carrier signal to and from a power cable, transmission and reception of information can be readily realized without providing a communication line separately.    Patent document 1: Japanese Patent Laying-Open No. 10-262303    Patent document 2: Japanese Patent Laying-Open No. 2006-262570